Adding .gitlab-ci.yml file for documentation.

.gitlab-ci.yml

+image: ligo/software:stretch
+
+variables:
+  DOCKER_DRIVER: overlay
+  BRANCH: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME
+  COMMIT: $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
+  NIGHTLY: $CI_REGISTRY_IMAGE:nightly
+  TAG: $CI_REGISTRY_IMAGE:$CI_COMMIT_TAG
+  GSTLAL_DIR: $CI_PROJECT_DIR/opt/gstlal
+
+before_script:
+    #- docker login -u gitlab-ci-token -p $CI_JOB_TOKEN $CI_REGISTRY
+    - export PATH="${GSTLAL_DIR}/bin:${PATH}"
+    - export PKG_CONFIG_PATH="${GSTLAL_DIR}/lib/pkgconfig:${GSTLAL_DIR}/lib64/pkgconfig:${PKG_CONFIG_PATH}"
+    - export GI_TYPELIB_PATH="${GSTLAL_DIR}/lib/girepository-1.0:${GI_TYPELIB_PATH}"
+    - export GST_PLUGIN_PATH="/opt/gstlal/lib/gstreamer-1.0:${GST_PLUGIN_PATH}"
+    - export PYTHONPATH="${GSTLAL_DIR}/lib64/python2.7/site-packages:${GSTLAL_DIR}/lib/python2.7/site-packages:${PYTHONPATH}"
+    - export GSTLAL_FIR_WHITEN=1
+
+stages:
+    - nightly-pages
+
+pages:
+  #Build from the nightly lalsuite container:
+  image: containers.ligo.org/lscsoft/lalsuite:nightly
+  stage: nightly-pages
+  script:
+    - mkdir public
+    - echo "Building GstLAL"
+    - apt update
+    # Pull installation dependencies:
+    - apt-get --assume-yes install automake
+    # Pull GstLAL-specific dependencies:
+    - apt-get --assume-yes install doxygen gtk-doc-tools libfftw3-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev liborc-0.4-0 gobject-introspection python-gobject-dev python-numpy python-scipy lscsoft-gds
+    - cd gstlal; ./00init.sh; ./configure --prefix=${GSTLAL_DIR}; make; make install
+    - cd ../gstlal-ugly; ./00init.sh; ./configure --prefix=${GSTLAL_DIR}; make; make install
+    - cd ../gstlal-calibration; ./00init.sh; ./configure --prefix=${GSTLAL_DIR}; make; make install
+    - cd ../gstlal-inspiral; ./00init.sh; ./configure --prefix=${GSTLAL_DIR}; make; make install
+    - echo "Building Documentation"
+    - apt-get --assume-yes install python-sphinx
+    - export TMPDIR=tmp/
+    - cd ../doc; make html
+    - cd ..; cp -rf doc/_build/* public/
+    
+  dependencies: []
+  artifacts:
+    paths:
+      - public
+  only:
+    - master@alexander-pace/gstlal
+    - pushes
+  except:
+    - web
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